This invention relates generally to electric motors and more particularly, to an endshield assembly for an electric motor.
Known electric motors typically include a motor housing, a stator, and a rotor assembly The rotor assembly includes a rotor core and a rotor shaft extending through the core. The housing includes a shell and two endshields and houses at least a portion of the rotor assembly. Electric motors also include at least one bearing sized to receive the rotor shaft. Typically the bearings are coupled to the endshields with springs, brackets or other mountings. The endshields attach to ends of the housing shell. For optimum operation of the motor, the bearings need to align with the rotor shaft, i.e., the center of the bearing cartridge opening needs to align with the centerline of the rotor shaft.
Each part of the endshield and bearing assembly is manufactured to a tolerance, and the tolerance of the assembly is the sum of the tolerances of the parts. Known cartridge bearing and endshield mounting configurations result in additive tolerances. Additive tolerances of the parts of the assembly can result in misaligned bearings and associated wear and motor performance problems.
It would be desirable to provide an endshield and bearing assembly that would not produce additive tolerances, therefore, resulting in lower tolerances in the final motor assembly. It would also be desirable to provide an endshield and bearing assembly that has a reduced number of parts and that provides accurate support of the bearing element and that permits limited bearing alignment.